This circuit can easily be assembled on a small piece of prototyping board. Use low-current types for the LEDs. They have a low forward voltage and are fairly bright at current levels as low as 1 mA.

Sound is pressure — the louder the sound, the greater the pressure. The greater the pressure, the more damage it can do to your ears. If you’re in a noisy environment, it’s important to know how ...

Today we are looking at the best decibel meter app to measure noise levels. Do you work in a loud factory and want to see just how much damage is happening to your ears when you “forget” your earplugs ...